1,433 research outputs found
On integrating a proprietary and a commercial architecture for optimal BIST performances in SoCs
This paper presents the integration of a proprietary hierarchical and distributed test access mechanism called HD2BIST and a BIST insertion commercial tool. The paper briefly describes the architecture and the features of both the environments and it presents some experimental results obtained on an industrial So
Human replication protein A can suppress the intrinsic in vitro mutator phenotype of human DNA polymerase λ
DNA polymerase λ (pol λ) is a member of the X family DNA polymerases and is endowed with multiple enzymatic activities. In this work we investigated the in vitro miscoding properties of full-length, human pol λ either in the absence or in the presence of the human auxiliary proteins proliferating cell nuclear antigen (PCNA) and replication protein A (RP-A). Our data suggested that (i) pol λ had an intrinsic ability to create mismatches and to incorporate ribonucleotides at nearly physiological Mn++ and Mg++ concentrations; (ii) the sequence of the template-primer could influence the misincorporation frequency of pol λ; (iii) pol λ preferentially generated G:T and G:G mismatches; (iv) RP-A, but not PCNA, selectively prevented misincorporation of an incorrect nucleotide by pol λ, without affecting correct incorporation and (v) this inhibitory effect required a precise ratio between the concentrations of pol λ and RP-A. Possible physiological implications of these findings for the in vivo fidelity of pol λ are discusse
Human replication protein A can suppress the intrinsic in vitro mutator phenotype of human DNA polymerase λ
DNA polymerase λ (pol λ) is a member of the X family DNA polymerases and is endowed with multiple enzymatic activities. In this work we investigated the in vitro miscoding properties of full-length, human pol λ either in the absence or in the presence of the human auxiliary proteins proliferating cell nuclear antigen (PCNA) and replication protein A (RP-A). Our data suggested that (i) pol λ had an intrinsic ability to create mismatches and to incorporate ribonucleotides at nearly physiological Mn(++) and Mg(++) concentrations; (ii) the sequence of the template-primer could influence the misincorporation frequency of pol λ; (iii) pol λ preferentially generated G:T and G:G mismatches; (iv) RP-A, but not PCNA, selectively prevented misincorporation of an incorrect nucleotide by pol λ, without affecting correct incorporation and (v) this inhibitory effect required a precise ratio between the concentrations of pol λ and RP-A. Possible physiological implications of these findings for the in vivo fidelity of pol λ are discussed
Metabolic Markers Following Beta-adrenoceptor Agonist Infusion In Footshock-stressed Rats.
Stress hormones can alter metabolic functions in adipose tissue and liver, as well as the sensitivity of rat white adipocytes and rat atrial responses to beta-adrenergic agonists. In this study, we examined the effects of three daily footshock stress sessions on the plasma corticosterone, glucose, glycerol and triacylglycerol levels of fed, conscious male rats, and on the plasma glucose, glycerol and triacylglycerol levels of the same rats following iv infusions of beta-adrenergic agonists (isoproterenol: 0.4 nmol kg-1 min-1, noradrenaline: 5.0 microg kg-1 day-1, and BRL 37344 ([+/-]-[4-(2-[(2-[3-chlorophenyl]-2-hydroxyethyl)amino]propyl)phenoxy]acetic acid), a selective beta3-adrenoceptor agonist: 0.4 nmol kg-1 min-1). Plasma corticosterone levels increased significantly after each stress session, while triacylglycerol levels increased after the first session and glucose increased after the second and third sessions. Glycerol levels were unaltered after stress. These results suggest that repeated footshock stress may induce a metabolic shift from triacylglycerol biosynthesis to glucose release by hepatic tissue, with glycerol serving as one of the substrates in both pathways. Stressed rats were more sensitive to infusion of noradrenaline plus prazosin and to infusion of isoproterenol, with elevated plasma glucose, glycerol and triacylglycerol levels. The higher sensitivity of stressed rats to isoproterenol and noradrenaline was probably related to the permissive effect of plasma corticosterone. Only BRL 37344 increased plasma glycerol levels in stressed rats, probably because beta3-adrenoceptors are not involved in hepatic triacylglycerol synthesis, thus allowing glycerol to accumulate in plasma.341197-20
Equine Bone Marrow and Adipose Tissue Mesenchymal Stem Cells: Cytofluorimetric Characterization, In Vitro Differentiation, and Clinical Application
The aim of the present work was to isolate, cultivate, differentiate, and conduct cellular
characterization of mesenchymal stem cells (MSCs) derived from equine adipose tissue
(eAT) and bone marrow (eBM). Isolated and characterized cells were used in racehorses
suffering from a superficial flexor tendon injury. Equine adipose tissue collection was
performed at the base of the horse tail, whereas eBM was aspirated from iliac crest.
Mononuclear cell fraction was isolated and cultured. In vitro differentiation and molecular
characterization at P3 of culture were performed. No statistically significant differences in
the number of cell doublings were found among different culture passages (P > .05).
Doubling time was greater for eBM than eAT (3.2 1.5 vs. 1.3 0.7; P < .05). Positive von
Kossa and Alizarin Red staining confirmed osteogenesis. Alcian Blue and Oil Red O staining
illustrated chondrogenesis and adipogenesis, respectively. Isolated cells resulted positive
for CD90, CD44, and CD105, whereas negative for hematopoietic markers, CD14, CD45, and
CD34. Using isolated cells for injured tendon therapy, no adverse reactions were observed,
and all inoculated horses returned to race competitions. In vitro results revealed the
immunophenotypic characterization of isolated cells similar to that observed in human
MSCs from the same sources; furthermore, in the present study, their clinical use proves
the safety of eBM-derived and eAT-derived MSCs and a successful outcome for the treated
animals that returned to their previous level of sport activity
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